Hydrogen peroxide, activation

The results showed that honey with an average level of hydrogen peroxide activity is bacteriostatic at 4 to 8% (v/v) and bactericidal at 5 to 10% (v/v). The nonperoxide activity of an average manuka honey is bacteriostatic at 5 to 11% (v/v) and bactericidal at 8 to 15% (v/v). Activity (just bacteriostatic) was not seen with artificial honey unless it was at 20 to 30% (v/v), clearly showing the importance of factors other than sugar and acidity. 

Application of fluid-state PC in a liposomal form significantly decreased both the microcirculation in the dermis,25 and the erythema induced by UVB-light.26 The latter result could be explained by a series of reactions in which UVB-light induced generation of hydrogen peroxide, activation of PLD,27 and formation of PC metabolites with anti-inflammatory effects.16... 

Two other hydrogen peroxide activation routes which need to be mentioned in this section are Caro s acid and the generation of halogens with hydrogen peroxide. The general schemes for their manufacture are shown in Figure 2.34. 

Peroxygens Hydrogen peroxide activity results from formation of free hydroxyl radicals ( OH) which oxidize thiol groups in enzymes and proteins Peracetic acid disrupts thiol groups in proteins and enzymes... 

Takada Y, Mukhopadhyay A, Kundu GC, Mahabeleshwar GH, Singh S (2003) Hydrogen peroxide activates NF-kappa B through tyrosine phosphorylation of I kappa B alpha and serine phosphorylation of p65 evidencefortheinvolvement of I kappa B alpha kinase and Syk protein-tyro sine kinase. J Biol Chem 278 24233-24241... 

Figure 16 Suggested reaction scheme for hydrogen peroxide activation in heme peroxidases.

C. Fickert, W. Kiefer, Peroxomolybdenum complexes as epoxidation catalysts in biphasic hydrogen peroxide activation Raman spectroscopic studies and density functional calculations, Chem. Eur. J. 5 (1999) 3237. 

H. Munakata, Y. Oumi, A. Miyamoto, A DET study on peroxo-complex in titanosilicate catalyst Hydrogen peroxide activation on titanosilicalite-1 catalyst and reaction mechanisms for catalytic olefin epoxidation and for hydroxylamine formation from ammonia, J. Phys. Chem. B 105 (2001) 3493. 

Zhang, J., Johnston, G., Stebler, B., and Keller, E.T. (2001). Hydrogen peroxide activates NFkappaB and the interleukin-6 promoter through NFkappaB-inducing kinase. Antioxid Redox Signal, 3(3) 493-504. 

V Kubelka, RC Erancis, CW Dence. Delignification with acidic hydrogen peroxide activated by molybdate. J Pulp Pap Sci 18 1108-1114, 1992. 

CHT Activator NB. [Catawba-Charlab] Hydrogen peroxide activate for low pH bleaching. 

The incorporation of an activated bleach system into an HDL is still one of the biggest challenges in formulation technology, as the three basic components of a bleach system (hydrogen peroxide, activator or catalyst, and alkalinity) will normally decompose as soon as they come into contact with each other. 

For disinfection hydrogen peroxide is used. To decompose the hydrogen peroxide activated carbon is used as a catalyst. In this application the choice of the activated carbon type is not very critical. Dependent of the fact whether some leaching of mineral is allowed a washed or unwashed type is applied. 

Arene oxide intermediates were postulated for the acid-catalyzed oxidation of arenes by dimeth-yldioxirane [46] and aromatic hydroxylations with hydrogen peroxide activated by methylrhenium trioxide (MTO, CH ReOj) [47,48]. Scheme 14.9 shows a proposed mechanism for pseudocumene (PC) oxidation with the MTO/H O system. 

---